The Monster likely represents the biggest species of pliosaur known to science, said Jxrn Hurum, of the Natural History Museum in Oslo, Norway, who led the dig teamand who called the reptile "the T. rex of the ocean."

Pliosaurs were the top marine predators during the Jurassic period (200 to 145 million years ago), but their fossils are rarely found.

The Monster is portrayed here leaping after a pterosaur, but the creature's main prey was likely other large sea reptiles.